As PC-based social networking applications such as Facebook and MySpace have soared in popularity, social networking tools are now being incorporated into many kinds of online spaces. It is clear that many people have a desire to create, maintain, and display their social connections. PC-based social networking applications have demonstrated that digital media can support these desires quite effectively. However, PC-based social networks have a number of limiting characteristics. First, PC-based social networks are tied to the conventions of the graphical user interface (GUI), keyboard, and mouse. While the GUI paradigm is without doubt hugely successful and important, its limitations have been well documented [see, e.g. Klemmer, S., Hartmann, B., Takayama, L., “How bodies matter: five themes for interaction design,” Proceedings of the 6th ACM conference on Designing Interactive systems, New York, N.Y., USA, ACM Press (2006), 140-149]. These include, for example, poor ability to support collaborative work, single point of control (the cursor), poor ability to properly take advantage of foreground and background attention, and homogenization of task execution [Ishii, H., Ullmer, B., “Tangible bits: towards seamless interfaces between people, bits and atoms,” CHI '97: Proceedings of the SIGCHI conference on Human factors in computing systems, New York, N.Y., USA, ACM Press (1997), 234-241]. Especially for social applications, the failure of GUI-based interactions to seamlessly and ambiently integrate into the user's physical world reduces their power to support a user's social behavior, which is behavior that often occurs, and until recently always occurred, in the physical realm.
PC-based social networks also often induce social behavior that strongly differs from behavior found in the physical world, most likely due to the ways in which purely virtual spaces differ from physical ones. For example, in virtual settings, identities can easily shift and multiply, message cost is almost nil, in that a message can be just as easily sent to a thousand people as to one, and information is generally freely available and searchable by the public [Donath, J., Boyd, D., “Public displays of connection”, BT Technology Journal (2004) 22(4):71-82]. It is common to find users who have literally thousands of friends in an online space, even though such a number would seem ridiculous in terms of physical space. While more in-depth analyses provide some reasons for this [Boyd, D., “Friends, Friendsters, and Top 8: Writing Community into being on social network sites,” First Monday (2003), 11(12)], it suffices to note that social networks in the virtual realm need not strongly correlate with social networks situated in the physical realm. By no means are these characteristics inherently bad, but they do suggest a significant break from pre-digital forms of social behavior.
The way in which users create a social network through forming links using a web-based application varies from application to application, and the signaling cost varies as well. In general, though, link formation is mediated by an explicit invitation process. A user first creates a profile, filling in personal information and the like. She can then invite friends. For example, the user types in a potential friend's email address and invites them to join her social network by clicking a button. The recipient will receive the invitation, usually via email, and can choose to accept or decline the link, also via a button click. The cost to produce a link then, is relatively low: a few clicks by both users, plus their willingness to send and accept the invitation. Declining links, however, is often perceived as rude. This fact tends to positively bias the creation of social links, as users would rather live with a weak link in their profile than upset the inviter. Donath and Boyd provide trenchant analyses of link formation, noting that the “friendships” formed on social networking sites are not equivalent to those found in the physical social milieu [Danah Boyd, “Friends, Friendsters, and Top 8: Writing Community into being on social network sites.” First Monday, 11(12), December 2006; J. Donath and D. Boyd, “Public displays of connection,” BT Technology Journal, 22(4):71-82, 2004]. Boyd lists thirteen factors people give for forming links, or “Friending,” only three of which involve actual acquaintance with the person to-be-linked.
A great deal of theoretical and empirical scholarship has explored the ways in which people attach meaning to physical objects [See, e.g., Csikszentmihalyi, M., Rochberg-Halton, E., “The meaning of things: domestic symbols and the self,” Cambridge University Press (1981)]. Following some of this work, social objects are defined to be a physical object in which the symbolic value of the object lies in how it represents a social relationship or relationships. A wedding ring is a fine example: its role is chiefly symbolic and it symbolizes the commitment two spouses make to one another. A social object can also symbolize wider group membership; for example, fraternity pins and military dog tags serve this function. Social objects are thus intimately entwined with our social lives; they serve as physical referents to our relationships and influence how we construct and maintain those relationships.
Some prior work has explored how physical objects acquire meaning and how designers can engage these meanings with tangible user interfaces. For example, Chang et. al. explore the power of objects as intimate communication channels with “LumiTouch” [Chang, A., Resner, B., Koerner, B., Wang, X., Ishii, H., “Lumitouch: an emotional communication device,” CHI '01: extended abstracts on Human factors in computing systems, New York, N.Y., USA, ACM Press (2001), 313-314]. This work recognizes that photographs often act as social objects. Chang et. al. embed tactile and visual affordances into photo frames, allowing them to act as direct, ambient communication channels. A user can touch force-sensitive pads on one frame, causing different patterns of light to appear on a partnered frame. In this way, two people can connect over distance through objects that represent their relationship. LumiTouch thus reinforces the metaphorical role photographs already occupy. LumiTouch frames are explicitly coupled with particular people—the people represented by photographs in the partnered frames.
Elise van den Hoven and others have also argued that tangible interface research should include personal objects, or mementos [van den Hoven, E., Eggen, B., “Personal souvenirs as ambient intelligent objects,” sOc-EUSAI '05: Proceedings of the 2005 joint conference on Smart objects and ambient intelligence, New York, N.Y., USA, ACM Press (2005), 123-128]. Her work includes both theoretical discussions of this argument, as well as experiments with tangible interfaces that include mementos.
Mugellini et. al.'s Memodules explicitly cites these arguments [Mugellini, E., Rubegni, E., Gerardi, S., Abou Khaled, O., “Using personal objects as tangible interfaces for memory recollection and sharing,” TEI '07: Proceedings of the 1st international conference on Tangible and embedded interaction, New York, N.Y., USA, ACM Press (2007), 231-238]. Memodules lets users associate mementos with digital media. RFID tags are applied to a memento such as, for example, a seashell from a vacation to the beach. Using an RFID reader and a visual PC application, the object can be associated with arbitrary content. When placed on the reader later on, the object will conjure up that media based on the associations it has previously acquired. For example, a user could associate the seashell with sounds of the ocean and beach pictures; when the seashell is held over the memodules reader, the system plays back the ocean sounds and displays the beach pictures. The Memodules system represents an attempt to augment pre-existing, inert physical objects—instead of conjuring memories in the mind of the user, the mementos can conjure media in the user's physical environment.
Barry's Story Beads introduced a new kind of object that has memento-like qualities [Barbara Barry and Glorianna Davenport, “StoryBeads: a wearable for story construction and trade”, MIT; Barry, B., “StoryBeads: a tool for distributed and mobile storytelling”, MIT MS Thesis (2000)]. StoryBeads consists of small beads that can be strung together, each of which contain static EEPROM memory that is used to store images. A larger amulet bead can be connected with the image beads. This amulet includes an LCD screen and a simple interface. The interface permits the user to view the images stored on the beads. The beads can be traded among users and images can be transferred from bead to bead. A desktop GUI lets users transfer fresh images onto the beads themselves, as well as associate the images with metadata. StoryBeads seeks to establish a link between the physical beads and the narrative data they contain, as well as to explore how groups of beads can be viewed as whole narratives and be used to build new narratives. In this sense, Barry is exploring how physical objects can be associated with personal, social information, and how the physical objects might afford ways of understanding and manipulating that information. StoryBeads need not represent social relationships and they do not function to create communication channels between users.
Kikin-Gil has created a design prototype for a different bead system that supports social communication. Her “BuddyBeads” [Kikin-Gil, R., “BuddyBeads: techno-jewelry for non verbal communication within groups of teenage girls”, Proceedings of the 7th international conference on Human computer interaction with mobile devices & services (2005), 375-376] are strung together as a bracelet. Each bead is associated with either a person or an agreed-upon message. A user can make the message beads of different members of the group vibrate by pressing on message and person beads on her bracelet. The beads as a whole act to link a network of people via dedicated physical objects, but do not purport to allow users to explore social links beyond those in their bracelet. It is not clear whether the BuddyBeads system was ever fully implemented.
As a class project at the MIT Media Lab, Norton, Liu and Laibowitz prototyped a system and coined the term “tangible social network” [Laibowitz, M., Norton, K., Liu, M., “Clique”, MIT class project, 2004]. Their “Clique” system consisted of customizable, tradable dolls, each doll representing its creator. These dolls were to be exchanged among a group of friends. These dolls thus act as social objects, by both explicitly representing their creators, and by being gifts. The dolls would be placed on a special table that could take note of their relative positions and project this information onto a nearby wall or screen. Users could associate data with the dolls, as well as turn the doll's heads, perhaps to indicate their current feelings about the represented friends.
Camerer points out that gifts are a specific type of object that is likely to shape social relationships [Camerer, C., “Gifts as Economic Signals and Social Symbol”, The American Journal of Sociology (1988), 94:180-214]. Gifts can be treated as signals of one's investment in another person. Put simply, a good gift is a physical symbol of a social relationship. Any gift contains information about the relationship between the giver and the receiver. First and foremost, each gift denotes the existence of a social link between two people. Second, the cost of the gift—how much time, money and knowledge are required to acquire and present it—represents the strength of that relationship.
Gifts can therefore sketch out the links of a social network. If this information can be captured, it can be used to document social networks that have more detail and greater consonance with a user's “reality-based” social network than current internet-based social network applications. Social networks can also be built up automatically, without forcing users to build their networks from scratch via clicks and email invitations, such as is currently required by internet-based social networks. These features would remove the barriers to entry and use that PC-based social networks entail, and would thus permit natural integration of social networking into a larger group of people's lives. Further, if this information could be captured with the implicit permission of the user, the privacy problems raised by data-mining methods for social network discovery would be avoided. Finally, a system that consists of communicative social objects—objects that provide a communication channel between the givers and receivers—would “close the loop” on the social networking application: instead of just allowing people to observe social network structures, a medium could be provided for social communication and display. Such a system would provide a complete social network application: a medium for exploring and building social networks.